Which of the Following Statements Are True of Vectors and the Diseases

Which of the following statements are true of vectors and the diseases they spread (Select all that apply) ?

A) The human body louse is the vector of typhoid fever.
B) Mosquitoes are vectors of malaria and yellow fever.
C) Vectors spread disease when they bite humans or other warm-blooded animals.
D) The deer tick is the vector of Lyme disease and West Nile encephalitis.
E) Fleas are vectors of bubonic plague,epidemic typhus,and sleeping sickness.
F) The vector of a pathogen may be an essential part of the life cycle of that pathogen.